SAR reduction using dual band EBG method based on MIMO wearable antenna for WBAN applications

A wearable ultra-wideband MIMO antenna using conductor and polyester fiber fabrics is proposed in this paper. The antenna’s total dimension is 115 × 70 mm2. As a result, the antenna can be installed on curved or bent surfaces due to its flexibility. This proposed antenna has a frequency range of 2 GHz – 30 GHz, a gain of 3.75 dBi on average, and a correlation coefficient of 0.5. That can be utilized for interior installation of the 5G frequency spectrum (2.6 GHz and 26 GHz), as well as WBAN application (2.4 GHz, 5.2 GHz, and 3.1 GHz – 10.6 GHz). Additionally, the researchers designed an electromagnetic band gap (EBG) and constructed a square loop plate with a square plate that reflects resonance characteristics in the 2.4 GHz and 5.2 GHz bands by placing unit cells in 3 × 5 cells to decrease the antenna’s specific absorption rate (SAR). The proposed antenna with EBG could minimize the SAR values to 0.088 W/kg and 0.070 W/kg, which obtains a gain of 6.59 dBi and 11.6 dBi, at 2.4 GHz and 5.2 GHz, respectively. Also, the results are lower than the conventional SAR value of 2.0 W/kg at 10 g.